Properly compute redundancy_bytes
[opus.git] / silk / control_codec.c
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26 ***********************************************************************/
27
28 #ifdef HAVE_CONFIG_H
29 #include "config.h"
30 #endif
31 #ifdef FIXED_POINT
32 #include "main_FIX.h"
33 #define silk_encoder_state_Fxx      silk_encoder_state_FIX
34 #else
35 #include "main_FLP.h"
36 #define silk_encoder_state_Fxx      silk_encoder_state_FLP
37 #endif
38 #include "stack_alloc.h"
39 #include "tuning_parameters.h"
40 #include "pitch_est_defines.h"
41
42 static opus_int silk_setup_resamplers(
43     silk_encoder_state_Fxx          *psEnc,             /* I/O                      */
44     opus_int                        fs_kHz              /* I                        */
45 );
46
47 static opus_int silk_setup_fs(
48     silk_encoder_state_Fxx          *psEnc,             /* I/O                      */
49     opus_int                        fs_kHz,             /* I                        */
50     opus_int                        PacketSize_ms       /* I                        */
51 );
52
53 static opus_int silk_setup_complexity(
54     silk_encoder_state              *psEncC,            /* I/O                      */
55     opus_int                        Complexity          /* I                        */
56 );
57
58 static OPUS_INLINE opus_int silk_setup_LBRR(
59     silk_encoder_state              *psEncC,            /* I/O                      */
60     const silk_EncControlStruct     *encControl         /* I                        */
61 );
62
63
64 /* Control encoder */
65 opus_int silk_control_encoder(
66     silk_encoder_state_Fxx          *psEnc,                                 /* I/O  Pointer to Silk encoder state                                               */
67     silk_EncControlStruct           *encControl,                            /* I    Control structure                                                           */
68     const opus_int                  allow_bw_switch,                        /* I    Flag to allow switching audio bandwidth                                     */
69     const opus_int                  channelNb,                              /* I    Channel number                                                              */
70     const opus_int                  force_fs_kHz
71 )
72 {
73     opus_int   fs_kHz, ret = 0;
74
75     psEnc->sCmn.useDTX                 = encControl->useDTX;
76     psEnc->sCmn.useCBR                 = encControl->useCBR;
77     psEnc->sCmn.API_fs_Hz              = encControl->API_sampleRate;
78     psEnc->sCmn.maxInternal_fs_Hz      = encControl->maxInternalSampleRate;
79     psEnc->sCmn.minInternal_fs_Hz      = encControl->minInternalSampleRate;
80     psEnc->sCmn.desiredInternal_fs_Hz  = encControl->desiredInternalSampleRate;
81     psEnc->sCmn.useInBandFEC           = encControl->useInBandFEC;
82     psEnc->sCmn.nChannelsAPI           = encControl->nChannelsAPI;
83     psEnc->sCmn.nChannelsInternal      = encControl->nChannelsInternal;
84     psEnc->sCmn.allow_bandwidth_switch = allow_bw_switch;
85     psEnc->sCmn.channelNb              = channelNb;
86
87     if( psEnc->sCmn.controlled_since_last_payload != 0 && psEnc->sCmn.prefillFlag == 0 ) {
88         if( psEnc->sCmn.API_fs_Hz != psEnc->sCmn.prev_API_fs_Hz && psEnc->sCmn.fs_kHz > 0 ) {
89             /* Change in API sampling rate in the middle of encoding a packet */
90             ret += silk_setup_resamplers( psEnc, psEnc->sCmn.fs_kHz );
91         }
92         return ret;
93     }
94
95     /* Beyond this point we know that there are no previously coded frames in the payload buffer */
96
97     /********************************************/
98     /* Determine internal sampling rate         */
99     /********************************************/
100     fs_kHz = silk_control_audio_bandwidth( &psEnc->sCmn, encControl );
101     if( force_fs_kHz ) {
102        fs_kHz = force_fs_kHz;
103     }
104     /********************************************/
105     /* Prepare resampler and buffered data      */
106     /********************************************/
107     ret += silk_setup_resamplers( psEnc, fs_kHz );
108
109     /********************************************/
110     /* Set internal sampling frequency          */
111     /********************************************/
112     ret += silk_setup_fs( psEnc, fs_kHz, encControl->payloadSize_ms );
113
114     /********************************************/
115     /* Set encoding complexity                  */
116     /********************************************/
117     ret += silk_setup_complexity( &psEnc->sCmn, encControl->complexity  );
118
119     /********************************************/
120     /* Set packet loss rate measured by farend  */
121     /********************************************/
122     psEnc->sCmn.PacketLoss_perc = encControl->packetLossPercentage;
123
124     /********************************************/
125     /* Set LBRR usage                           */
126     /********************************************/
127     ret += silk_setup_LBRR( &psEnc->sCmn, encControl );
128
129     psEnc->sCmn.controlled_since_last_payload = 1;
130
131     return ret;
132 }
133
134 static opus_int silk_setup_resamplers(
135     silk_encoder_state_Fxx          *psEnc,             /* I/O                      */
136     opus_int                         fs_kHz              /* I                        */
137 )
138 {
139     opus_int   ret = SILK_NO_ERROR;
140     SAVE_STACK;
141
142     if( psEnc->sCmn.fs_kHz != fs_kHz || psEnc->sCmn.prev_API_fs_Hz != psEnc->sCmn.API_fs_Hz )
143     {
144         if( psEnc->sCmn.fs_kHz == 0 ) {
145             /* Initialize the resampler for enc_API.c preparing resampling from API_fs_Hz to fs_kHz */
146             ret += silk_resampler_init( &psEnc->sCmn.resampler_state, psEnc->sCmn.API_fs_Hz, fs_kHz * 1000, 1 );
147         } else {
148             VARDECL( opus_int16, x_buf_API_fs_Hz );
149             VARDECL( silk_resampler_state_struct, temp_resampler_state );
150 #ifdef FIXED_POINT
151             opus_int16 *x_bufFIX = psEnc->x_buf;
152 #else
153             VARDECL( opus_int16, x_bufFIX );
154             opus_int32 new_buf_samples;
155 #endif
156             opus_int32 api_buf_samples;
157             opus_int32 old_buf_samples;
158             opus_int32 buf_length_ms;
159
160             buf_length_ms = silk_LSHIFT( psEnc->sCmn.nb_subfr * 5, 1 ) + LA_SHAPE_MS;
161             old_buf_samples = buf_length_ms * psEnc->sCmn.fs_kHz;
162
163 #ifndef FIXED_POINT
164             new_buf_samples = buf_length_ms * fs_kHz;
165             ALLOC( x_bufFIX, silk_max( old_buf_samples, new_buf_samples ),
166                    opus_int16 );
167             silk_float2short_array( x_bufFIX, psEnc->x_buf, old_buf_samples );
168 #endif
169
170             /* Initialize resampler for temporary resampling of x_buf data to API_fs_Hz */
171             ALLOC( temp_resampler_state, 1, silk_resampler_state_struct );
172             ret += silk_resampler_init( temp_resampler_state, silk_SMULBB( psEnc->sCmn.fs_kHz, 1000 ), psEnc->sCmn.API_fs_Hz, 0 );
173
174             /* Calculate number of samples to temporarily upsample */
175             api_buf_samples = buf_length_ms * silk_DIV32_16( psEnc->sCmn.API_fs_Hz, 1000 );
176
177             /* Temporary resampling of x_buf data to API_fs_Hz */
178             ALLOC( x_buf_API_fs_Hz, api_buf_samples, opus_int16 );
179             ret += silk_resampler( temp_resampler_state, x_buf_API_fs_Hz, x_bufFIX, old_buf_samples );
180
181             /* Initialize the resampler for enc_API.c preparing resampling from API_fs_Hz to fs_kHz */
182             ret += silk_resampler_init( &psEnc->sCmn.resampler_state, psEnc->sCmn.API_fs_Hz, silk_SMULBB( fs_kHz, 1000 ), 1 );
183
184             /* Correct resampler state by resampling buffered data from API_fs_Hz to fs_kHz */
185             ret += silk_resampler( &psEnc->sCmn.resampler_state, x_bufFIX, x_buf_API_fs_Hz, api_buf_samples );
186
187 #ifndef FIXED_POINT
188             silk_short2float_array( psEnc->x_buf, x_bufFIX, new_buf_samples);
189 #endif
190         }
191     }
192
193     psEnc->sCmn.prev_API_fs_Hz = psEnc->sCmn.API_fs_Hz;
194
195     RESTORE_STACK;
196     return ret;
197 }
198
199 static opus_int silk_setup_fs(
200     silk_encoder_state_Fxx          *psEnc,             /* I/O                      */
201     opus_int                        fs_kHz,             /* I                        */
202     opus_int                        PacketSize_ms       /* I                        */
203 )
204 {
205     opus_int ret = SILK_NO_ERROR;
206
207     /* Set packet size */
208     if( PacketSize_ms != psEnc->sCmn.PacketSize_ms ) {
209         if( ( PacketSize_ms !=  10 ) &&
210             ( PacketSize_ms !=  20 ) &&
211             ( PacketSize_ms !=  40 ) &&
212             ( PacketSize_ms !=  60 ) ) {
213             ret = SILK_ENC_PACKET_SIZE_NOT_SUPPORTED;
214         }
215         if( PacketSize_ms <= 10 ) {
216             psEnc->sCmn.nFramesPerPacket = 1;
217             psEnc->sCmn.nb_subfr = PacketSize_ms == 10 ? 2 : 1;
218             psEnc->sCmn.frame_length = silk_SMULBB( PacketSize_ms, fs_kHz );
219             psEnc->sCmn.pitch_LPC_win_length = silk_SMULBB( FIND_PITCH_LPC_WIN_MS_2_SF, fs_kHz );
220             if( psEnc->sCmn.fs_kHz == 8 ) {
221                 psEnc->sCmn.pitch_contour_iCDF = silk_pitch_contour_10_ms_NB_iCDF;
222             } else {
223                 psEnc->sCmn.pitch_contour_iCDF = silk_pitch_contour_10_ms_iCDF;
224             }
225         } else {
226             psEnc->sCmn.nFramesPerPacket = silk_DIV32_16( PacketSize_ms, MAX_FRAME_LENGTH_MS );
227             psEnc->sCmn.nb_subfr = MAX_NB_SUBFR;
228             psEnc->sCmn.frame_length = silk_SMULBB( 20, fs_kHz );
229             psEnc->sCmn.pitch_LPC_win_length = silk_SMULBB( FIND_PITCH_LPC_WIN_MS, fs_kHz );
230             if( psEnc->sCmn.fs_kHz == 8 ) {
231                 psEnc->sCmn.pitch_contour_iCDF = silk_pitch_contour_NB_iCDF;
232             } else {
233                 psEnc->sCmn.pitch_contour_iCDF = silk_pitch_contour_iCDF;
234             }
235         }
236         psEnc->sCmn.PacketSize_ms  = PacketSize_ms;
237         psEnc->sCmn.TargetRate_bps = 0;         /* trigger new SNR computation */
238     }
239
240     /* Set internal sampling frequency */
241     silk_assert( fs_kHz == 8 || fs_kHz == 12 || fs_kHz == 16 );
242     silk_assert( psEnc->sCmn.nb_subfr == 2 || psEnc->sCmn.nb_subfr == 4 );
243     if( psEnc->sCmn.fs_kHz != fs_kHz ) {
244         /* reset part of the state */
245         silk_memset( &psEnc->sShape,               0, sizeof( psEnc->sShape ) );
246         silk_memset( &psEnc->sCmn.sNSQ,            0, sizeof( psEnc->sCmn.sNSQ ) );
247         silk_memset( psEnc->sCmn.prev_NLSFq_Q15,   0, sizeof( psEnc->sCmn.prev_NLSFq_Q15 ) );
248         silk_memset( &psEnc->sCmn.sLP.In_LP_State, 0, sizeof( psEnc->sCmn.sLP.In_LP_State ) );
249         psEnc->sCmn.inputBufIx                  = 0;
250         psEnc->sCmn.nFramesEncoded              = 0;
251         psEnc->sCmn.TargetRate_bps              = 0;     /* trigger new SNR computation */
252
253         /* Initialize non-zero parameters */
254         psEnc->sCmn.prevLag                     = 100;
255         psEnc->sCmn.first_frame_after_reset     = 1;
256         psEnc->sShape.LastGainIndex             = 10;
257         psEnc->sCmn.sNSQ.lagPrev                = 100;
258         psEnc->sCmn.sNSQ.prev_gain_Q16          = 65536;
259         psEnc->sCmn.prevSignalType              = TYPE_NO_VOICE_ACTIVITY;
260
261         psEnc->sCmn.fs_kHz = fs_kHz;
262         if( psEnc->sCmn.fs_kHz == 8 ) {
263             if( psEnc->sCmn.nb_subfr == MAX_NB_SUBFR ) {
264                 psEnc->sCmn.pitch_contour_iCDF = silk_pitch_contour_NB_iCDF;
265             } else {
266                 psEnc->sCmn.pitch_contour_iCDF = silk_pitch_contour_10_ms_NB_iCDF;
267             }
268         } else {
269             if( psEnc->sCmn.nb_subfr == MAX_NB_SUBFR ) {
270                 psEnc->sCmn.pitch_contour_iCDF = silk_pitch_contour_iCDF;
271             } else {
272                 psEnc->sCmn.pitch_contour_iCDF = silk_pitch_contour_10_ms_iCDF;
273             }
274         }
275         if( psEnc->sCmn.fs_kHz == 8 || psEnc->sCmn.fs_kHz == 12 ) {
276             psEnc->sCmn.predictLPCOrder = MIN_LPC_ORDER;
277             psEnc->sCmn.psNLSF_CB  = &silk_NLSF_CB_NB_MB;
278         } else {
279             psEnc->sCmn.predictLPCOrder = MAX_LPC_ORDER;
280             psEnc->sCmn.psNLSF_CB  = &silk_NLSF_CB_WB;
281         }
282         psEnc->sCmn.subfr_length   = SUB_FRAME_LENGTH_MS * fs_kHz;
283         psEnc->sCmn.frame_length   = silk_SMULBB( psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr );
284         psEnc->sCmn.ltp_mem_length = silk_SMULBB( LTP_MEM_LENGTH_MS, fs_kHz );
285         psEnc->sCmn.la_pitch       = silk_SMULBB( LA_PITCH_MS, fs_kHz );
286         psEnc->sCmn.max_pitch_lag  = silk_SMULBB( 18, fs_kHz );
287         if( psEnc->sCmn.nb_subfr == MAX_NB_SUBFR ) {
288             psEnc->sCmn.pitch_LPC_win_length = silk_SMULBB( FIND_PITCH_LPC_WIN_MS, fs_kHz );
289         } else {
290             psEnc->sCmn.pitch_LPC_win_length = silk_SMULBB( FIND_PITCH_LPC_WIN_MS_2_SF, fs_kHz );
291         }
292         if( psEnc->sCmn.fs_kHz == 16 ) {
293             psEnc->sCmn.pitch_lag_low_bits_iCDF = silk_uniform8_iCDF;
294         } else if( psEnc->sCmn.fs_kHz == 12 ) {
295             psEnc->sCmn.pitch_lag_low_bits_iCDF = silk_uniform6_iCDF;
296         } else {
297             psEnc->sCmn.pitch_lag_low_bits_iCDF = silk_uniform4_iCDF;
298         }
299     }
300
301     /* Check that settings are valid */
302     silk_assert( ( psEnc->sCmn.subfr_length * psEnc->sCmn.nb_subfr ) == psEnc->sCmn.frame_length );
303
304     return ret;
305 }
306
307 static opus_int silk_setup_complexity(
308     silk_encoder_state              *psEncC,            /* I/O                      */
309     opus_int                        Complexity          /* I                        */
310 )
311 {
312     opus_int ret = 0;
313
314     /* Set encoding complexity */
315     silk_assert( Complexity >= 0 && Complexity <= 10 );
316     if( Complexity < 1 ) {
317         psEncC->pitchEstimationComplexity       = SILK_PE_MIN_COMPLEX;
318         psEncC->pitchEstimationThreshold_Q16    = SILK_FIX_CONST( 0.8, 16 );
319         psEncC->pitchEstimationLPCOrder         = 6;
320         psEncC->shapingLPCOrder                 = 12;
321         psEncC->la_shape                        = 3 * psEncC->fs_kHz;
322         psEncC->nStatesDelayedDecision          = 1;
323         psEncC->useInterpolatedNLSFs            = 0;
324         psEncC->NLSF_MSVQ_Survivors             = 2;
325         psEncC->warping_Q16                     = 0;
326     } else if( Complexity < 2 ) {
327         psEncC->pitchEstimationComplexity       = SILK_PE_MID_COMPLEX;
328         psEncC->pitchEstimationThreshold_Q16    = SILK_FIX_CONST( 0.76, 16 );
329         psEncC->pitchEstimationLPCOrder         = 8;
330         psEncC->shapingLPCOrder                 = 14;
331         psEncC->la_shape                        = 5 * psEncC->fs_kHz;
332         psEncC->nStatesDelayedDecision          = 1;
333         psEncC->useInterpolatedNLSFs            = 0;
334         psEncC->NLSF_MSVQ_Survivors             = 3;
335         psEncC->warping_Q16                     = 0;
336     } else if( Complexity < 3 ) {
337         psEncC->pitchEstimationComplexity       = SILK_PE_MIN_COMPLEX;
338         psEncC->pitchEstimationThreshold_Q16    = SILK_FIX_CONST( 0.8, 16 );
339         psEncC->pitchEstimationLPCOrder         = 6;
340         psEncC->shapingLPCOrder                 = 12;
341         psEncC->la_shape                        = 3 * psEncC->fs_kHz;
342         psEncC->nStatesDelayedDecision          = 2;
343         psEncC->useInterpolatedNLSFs            = 0;
344         psEncC->NLSF_MSVQ_Survivors             = 2;
345         psEncC->warping_Q16                     = 0;
346     } else if( Complexity < 4 ) {
347         psEncC->pitchEstimationComplexity       = SILK_PE_MID_COMPLEX;
348         psEncC->pitchEstimationThreshold_Q16    = SILK_FIX_CONST( 0.76, 16 );
349         psEncC->pitchEstimationLPCOrder         = 8;
350         psEncC->shapingLPCOrder                 = 14;
351         psEncC->la_shape                        = 5 * psEncC->fs_kHz;
352         psEncC->nStatesDelayedDecision          = 2;
353         psEncC->useInterpolatedNLSFs            = 0;
354         psEncC->NLSF_MSVQ_Survivors             = 4;
355         psEncC->warping_Q16                     = 0;
356     } else if( Complexity < 6 ) {
357         psEncC->pitchEstimationComplexity       = SILK_PE_MID_COMPLEX;
358         psEncC->pitchEstimationThreshold_Q16    = SILK_FIX_CONST( 0.74, 16 );
359         psEncC->pitchEstimationLPCOrder         = 10;
360         psEncC->shapingLPCOrder                 = 16;
361         psEncC->la_shape                        = 5 * psEncC->fs_kHz;
362         psEncC->nStatesDelayedDecision          = 2;
363         psEncC->useInterpolatedNLSFs            = 1;
364         psEncC->NLSF_MSVQ_Survivors             = 6;
365         psEncC->warping_Q16                     = psEncC->fs_kHz * SILK_FIX_CONST( WARPING_MULTIPLIER, 16 );
366     } else if( Complexity < 8 ) {
367         psEncC->pitchEstimationComplexity       = SILK_PE_MID_COMPLEX;
368         psEncC->pitchEstimationThreshold_Q16    = SILK_FIX_CONST( 0.72, 16 );
369         psEncC->pitchEstimationLPCOrder         = 12;
370         psEncC->shapingLPCOrder                 = 20;
371         psEncC->la_shape                        = 5 * psEncC->fs_kHz;
372         psEncC->nStatesDelayedDecision          = 3;
373         psEncC->useInterpolatedNLSFs            = 1;
374         psEncC->NLSF_MSVQ_Survivors             = 8;
375         psEncC->warping_Q16                     = psEncC->fs_kHz * SILK_FIX_CONST( WARPING_MULTIPLIER, 16 );
376     } else {
377         psEncC->pitchEstimationComplexity       = SILK_PE_MAX_COMPLEX;
378         psEncC->pitchEstimationThreshold_Q16    = SILK_FIX_CONST( 0.7, 16 );
379         psEncC->pitchEstimationLPCOrder         = 16;
380         psEncC->shapingLPCOrder                 = 24;
381         psEncC->la_shape                        = 5 * psEncC->fs_kHz;
382         psEncC->nStatesDelayedDecision          = MAX_DEL_DEC_STATES;
383         psEncC->useInterpolatedNLSFs            = 1;
384         psEncC->NLSF_MSVQ_Survivors             = 16;
385         psEncC->warping_Q16                     = psEncC->fs_kHz * SILK_FIX_CONST( WARPING_MULTIPLIER, 16 );
386     }
387
388     /* Do not allow higher pitch estimation LPC order than predict LPC order */
389     psEncC->pitchEstimationLPCOrder = silk_min_int( psEncC->pitchEstimationLPCOrder, psEncC->predictLPCOrder );
390     psEncC->shapeWinLength          = SUB_FRAME_LENGTH_MS * psEncC->fs_kHz + 2 * psEncC->la_shape;
391     psEncC->Complexity              = Complexity;
392
393     silk_assert( psEncC->pitchEstimationLPCOrder <= MAX_FIND_PITCH_LPC_ORDER );
394     silk_assert( psEncC->shapingLPCOrder         <= MAX_SHAPE_LPC_ORDER      );
395     silk_assert( psEncC->nStatesDelayedDecision  <= MAX_DEL_DEC_STATES       );
396     silk_assert( psEncC->warping_Q16             <= 32767                    );
397     silk_assert( psEncC->la_shape                <= LA_SHAPE_MAX             );
398     silk_assert( psEncC->shapeWinLength          <= SHAPE_LPC_WIN_MAX        );
399
400     return ret;
401 }
402
403 static OPUS_INLINE opus_int silk_setup_LBRR(
404     silk_encoder_state          *psEncC,            /* I/O                      */
405     const silk_EncControlStruct *encControl         /* I                        */
406 )
407 {
408     opus_int   LBRR_in_previous_packet, ret = SILK_NO_ERROR;
409
410     LBRR_in_previous_packet = psEncC->LBRR_enabled;
411     psEncC->LBRR_enabled = encControl->LBRR_coded;
412     if( psEncC->LBRR_enabled ) {
413         /* Set gain increase for coding LBRR excitation */
414         if( LBRR_in_previous_packet == 0 ) {
415             /* Previous packet did not have LBRR, and was therefore coded at a higher bitrate */
416             psEncC->LBRR_GainIncreases = 7;
417         } else {
418             psEncC->LBRR_GainIncreases = silk_max_int( 7 - silk_SMULWB( (opus_int32)psEncC->PacketLoss_perc, SILK_FIX_CONST( 0.4, 16 ) ), 2 );
419         }
420     }
421
422     return ret;
423 }